Turbine airfoils, such as vanes and blades, are hollow components that include numerous internal features, such as cooling channels. Such airfoils and the internal features are typically made by investment casting using a core to form the desired internal features. The thickness of an outer wall of the airfoil can be critical to the component's performance during engine operation. The thickness of the outer wall of the airfoil must be kept within design specifications. Accordingly, once the airfoil is cast, the thickness of the outer wall is measured to ensure that it is within acceptable tolerances.
However, obtaining an accurate measurement of the thickness of the outer wall may be difficult if the outer surface and/or the inner surface of the outer wall is contoured at the point of measurement, as is typically the case with turbine airfoils. In such case, error is introduced into the wall thickness measurement. Such error can be problematic, particularly if subsequent machining or other manufacturing operations are dependent on the accuracy of the measured the wall thickness. Consequently, an undesirably high correction factor may need to be accounted for in the design, thereby preventing the component from achieving its full performance potential.
Thus, there is a need for a system and method for more precisely measuring the wall thickness of a component.